"Again!" the Fire Lord shouted from the opposite side of the room as he slid down into a fighting stance. Zuko mirrored his father as he lowered himself into a crouch, arms outstretched, ready to receive the first attack. Fire Lord Ozai lunged forward, sending a wave of bright orange flames towards his son who, leaping from his position, parted the fire in the center, hollowing out a space just large enough for his body. He was lanky, with muscles still developing from his pre-teen years, but the certainty in his movements made up for whatever lack of strength he may have had. Without hesitation he punched out from his chest and a lick of fire raced towards his father who brushed it aside with a flick of his hand as if it were nothing more than smoke.
Zuko had always admired his father's bending; it was beautiful and graceful, yet powerful, nothing less than expected from a firebending master, let alone the ruler of the entire Fire Nation. Zuko had learned from him and from his sister, who everyone had said was a prodigy before she left for battle. His father hadn't wanted her to go; as first in line for the throne, Azula was too valuable to be lost to the war which had dragged on for 100 years. But she was also one of the most gifted firebenders in the country, if not the entire world, and for two years her help at the frontlines of battle had been indispensable. The pain of her loss was born anew every morning. Zuko would wake in the early morning as the sun rose and stained the dark nighttime sky pink and red, and just for a moment, he would listen to hear his sister going through her warm-ups out in the courtyard. But he was always disappointed, and this disappointment reminded of why he had to do what he had to do. Why he had to take down the Water Empire.
He kicked out then in a circle, using his arms to propel the rest of his body, and a ring of fire erupted around him, spreading quickly through the training room. His father narrowly cleared the top of the ring and had to somersault to the ground on the other side of it. Zuko took this opportunity to sprint closer and, when he was only feet away, conjured a fire dagger in his hand, which he brought downward in an arc to the back of his father's neck.
Lord Ozai did not dare look up. The fire was less than an inch from his skin.
"I surrender," he said to his son, who immediately stood up and extinguished his weapon. He held out a hand to his father who was panting, his face red and sweaty, much like Zuko's. The two looked at each other for a long moment. Then Ozai, putting a hand on his son's shoulder, said, "You're ready."
Zuko nodded, trying to look confident despite the surge of dread that had just risen in his chest. He was ready for this task. It was his duty. It had taken him two years to get to this moment, and he wasn't about to desert all his hard work and the reason for which he had done it just because he was nervous. But his father's face fell, as if he was second-guessing himself.
"Are you sure about this?"
Zuko stood straighter and nodded once more. No more hesitation. No more doubt. He would do this. He would avenge his sister and save the Nations. But all he said out loud was, "It is my destiny."